The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Wan Zongshun <mcuos.com@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sachin Kamat [Thu, 23 May 2013 00:37:40 +0000 (10:37 +1000)]
drivers/rtc/rtc-x1205.c: fix checkpatch issues
Fixes the following types of issues:
ERROR: do not use assignment in if condition
ERROR: open brace '{' following struct go on the same line
ERROR: else should follow close brace '}'
WARNING: please, no space before tabs
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sachin Kamat [Thu, 23 May 2013 00:37:39 +0000 (10:37 +1000)]
drivers/rtc/rtc-rs5c313.c: fix spacing related issues
Fixes the following types of checkpatch issues:
WARNING: please, no space before tabs
ERROR: space prohibited after that open parenthesis '('
ERROR: space prohibited before that close parenthesis ')'
ERROR: need consistent spacing around '>>' (ctx:VxW)
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sachin Kamat [Thu, 23 May 2013 00:37:38 +0000 (10:37 +1000)]
drivers/rtc/rtc-omap.c: include <linux/io.h> instead of <asm/io.h>
Use #include <linux/io.h> instead of <asm/io.h> as pointed out by
checkpatch.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: George G. Davis <gdavis@mvista.com> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sachin Kamat [Thu, 23 May 2013 00:37:34 +0000 (10:37 +1000)]
drivers/rtc/rtc-ds1511.c: fix issues related to spaces and braces
Fixes the following types of issues:
WARNING: please, no spaces at the start of a line
WARNING: braces {} are not necessary for single statement blocks
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sachin Kamat [Thu, 23 May 2013 00:37:33 +0000 (10:37 +1000)]
drivers/rtc/rtc-at91rm9200.c: include <linux/uaccess.h>
Silences the following checkpatch warning:
WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: Andrew Victor <linux@maxim.org.za> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sachin Kamat [Thu, 23 May 2013 00:37:32 +0000 (10:37 +1000)]
drivers/rtc/interface.c: fix checkpatch errors
Fixes the following types of errors:
ERROR: "foo* bar" should be "foo *bar"
ERROR: else should follow close brace '}'
WARNING: braces {} are not necessary for single statement blocks
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Cc: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Miklos Szeredi [Thu, 23 May 2013 00:37:31 +0000 (10:37 +1000)]
autofs4: translate pids to the right namespace for the daemon
The PID and the TGID of the process triggering the mount are sent to the
daemon. Currently the global pid values are sent (ones valid in the
initial pid namespace) but this is wrong if the autofs daemon itself is
not running in the initial pid namespace.
So send the pid values that are valid in the namespace of the autofs daemon.
The namespace to use is taken from the oz_pgrp pid pointer, which was set
at mount time to the mounting process' pid namespace.
If the pid translation fails (the triggering process is in an unrelated
pid namespace) then the automount fails with ENOENT.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Ian Kent <raven@themaw.net> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
autofs4: allow autofs to work outside the initial PID namespace
Enable autofs4 to work in a "container". oz_pgrp is converted from pid_t
to struct pid and this is stored at mount time based on the "pgrp=" option
or if the option is missing then the current pgrp.
The "pgrp=" option is interpreted in the PID namespace of the current
process. This option is flawed in that it doesn't carry the namespace
information, so it should be deprecated. AFAICS the autofs daemon always
sends the current pgrp, which is the default anyway.
The oz_pgrp is also set from the AUTOFS_DEV_IOCTL_SETPIPEFD_CMD ioctl.
This ioctl sets oz_pgrp to the current pgrp. It is not allowed to change
the pid namespace.
oz_pgrp is used mainly to determine whether the process traversing the
autofs mount tree is the autofs daemon itself or not. This function now
compares the pid pointers instead of the pid_t values.
One other use of oz_pgrp is in autofs4_show_options. There is shows the
virtual pid number (i.e. the one that is valid inside the PID namespace
of the calling process)
For debugging printk convert oz_pgrp to the value in the initial pid
namespace.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Ian Kent <raven@themaw.net> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Steven Rostedt [Thu, 23 May 2013 00:37:30 +0000 (10:37 +1000)]
init: remove permanent string buffer from do_one_initcall()
do_one_initcall() uses a 64 byte string buffer to save a message. This
buffer is declared static and is only used at boot up and when a module
is loaded. As 64 bytes is very small, and this function has very limited
scope, there's no reason to waste permanent memory with this string and
not just simply put it on the stack.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We observed this problem has been occurring since 2.6.30 with
fs/binfmt_elf.c: create_elf_tables()->get_random_bytes(), introduced by f06295b44c296c8f ("ELF: implement AT_RANDOM for glibc PRNG seeding").
/*
* Generate 16 random bytes for userspace PRNG seeding.
*/
get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes));
The patch introduces a wrapper around get_random_int() which has lower
overhead than calling get_random_bytes() directly.
With this patch applied:
$ cat /proc/sys/kernel/random/entropy_avail
2731
$ cat /proc/sys/kernel/random/entropy_avail
2802
$ cat /proc/sys/kernel/random/entropy_avail
2878
Analyzed by John Sobecki.
Signed-off-by: Jie Liu <jeff.liu@oracle.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Dilger <aedilger@gmail.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Arnd Bergmann <arnn@arndb.de> Cc: John Sobecki <john.sobecki@oracle.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Jakub Jelinek <jakub@redhat.com> Cc: Ted Ts'o <tytso@mit.edu> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Kees Cook <keescook@chromium.org> Cc: Ulrich Drepper <drepper@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Joe Perches [Thu, 23 May 2013 00:37:29 +0000 (10:37 +1000)]
checkpatch: warn when using gcc's binary constant ("0b") extension
The gcc extension for binary constants that start with 0b is only
supported with gcc version 4.3 or higher.
The kernel can still be compiled with earlier versions of gcc, so have
checkpatch emit a warning for these constants.
Restructure checkpatch's constant finding code a bit to support finding
these binary constants.
Signed-off-by: Joe Perches <joe@perches.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Whitcroft <apw@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Chanho Min [Thu, 23 May 2013 00:37:28 +0000 (10:37 +1000)]
lib/bitmap.c: speed up bitmap_find_free_region
In bitmap_find_free_region(), if we skip the all-ones words and find bits
in a not-all-ones word, we can improve performance of it.
For example, If bitmap_find_free_region() is called with order=0, First,
It scans bitmap array by the increment of long type, then find 1 free bit
within 1 long type value. In 32 bits system and 1024 bits size, in the
worst case, We need 1024 for-loops to find 1 free bit. But, If this is
applied, it takes 64 for-loops. Instead, It will be needed additional
if-comparison of every word and It can take time slightly as 'Test case
3'. But, In many cases, It will speed up significantly.
Test cases bellows show the time taken to execute bitmap_find_free_region()
before and after patch.
Test case 1: order is 0. all bits are one except that last one bit is zero.
before patch: 29727 ns
after patch: 2349 ns
Test case 2: order is 1. all bits are one except that last 2 contiguous bits
are zero.
before patch: 15475 ns
after patch: 2225 ns
Test case 3: order is 1. all words are not-all-ones and don't have 2 contiguous
bits except that last 2 contiguous are zero.
before patch: 15475 ns
after patch: 16131 ns
Signed-off-by: Chanho Min <chanho.min@lge.com> Cc: Nadia Yvette Chambers <nyc@holomorphy.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Joe Perches <joe@perches.com> Cc: anish singh <anish198519851985@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063100 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d06310 ("device-core: Ensure drvdata =
NULL when no driver is bound"). Thus, it is not needed to manually clear
the device driver data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Chuansheng Liu [Thu, 23 May 2013 00:37:26 +0000 (10:37 +1000)]
smp: Give WARN()ing when calling smp_call_function_many()/single() in serving irq
Currently the functions smp_call_function_many()/single() will give a
WARN()ing only in the case of irqs_disabled(), but that check is not
enough to guarantee execution of the SMP cross-calls.
In many other cases such as softirq handling/interrupt handling, the two
APIs still can not be called, just as the smp_call_function_many()
comments say:
* You must not call this function with disabled interrupts or from a
* hardware interrupt handler or from a bottom half handler. Preemption
* must be disabled when calling this function.
There is a real case for softirq DEADLOCK case:
CPUA CPUB
spin_lock(&spinlock)
Any irq coming, call the irq handler
irq_exit()
spin_lock_irq(&spinlock)
<== Blocking here due to
CPUB hold it
__do_softirq()
run_timer_softirq()
timer_cb()
call smp_call_function_many()
send IPI interrupt to CPUA
wait_csd()
Then both CPUA and CPUB will be deadlocked here.
So we should give a warning in the nmi, hardirq or softirq context as well.
Moreover, adding one new macro in_serving_irq() which indicates we are
processing nmi, hardirq or sofirq.
Signed-off-by: liu chuansheng <chuansheng.liu@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Tested-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Lai Jiangshan <eag0628@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
- fix comment indenting
- avoid inclusion of <asm/> files - use <linux/> where possible
- fix uniprocessor build (__dump_stack undefined)
- remove unneeded ifdef around smp.h inclusion
Cc: Alex Thorlton <athorlton@sgi.com> Cc: David S. Miller <davem@davemloft.net> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Robin Holt <holt@sgi.com> Cc: Russ Anderson <rja@sgi.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: athorlton@sgi.com Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Alex Thorlton [Thu, 23 May 2013 00:37:24 +0000 (10:37 +1000)]
dump_stack: serialize the output from dump_stack()
tAdd adds functionality to serialize the output from dump_stack() to avoid
mangling of the output when dump_stack is called simultaneously from
multiple cpus.
Signed-off-by: Alex Thorlton <athorlton@sgi.com> Reported-by: Russ Anderson <rja@sgi.com> Reviewed-by: Robin Holt <holt@sgi.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: David S. Miller <davem@davemloft.net> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Dan Carpenter [Thu, 23 May 2013 00:37:24 +0000 (10:37 +1000)]
err.h: IS_ERR() can accept __user pointers
Sparse generates a false positive when you pass a __user or __iomem
pointer to the IS_ERR() functions.
drivers/rtc/rtc-ds1286.c:344:36: sparse: incorrect type in argument 1 (different address spaces)
drivers/rtc/rtc-ds1286.c:344:36: expected void const *ptr
drivers/rtc/rtc-ds1286.c:344:36: got unsigned int [noderef] [usertype] <asn:2>*rtcregs
We can silence these by adding a __force here and upgrading to the
latest git release of Sparse.
This change has no effect when using current Sparse releases.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Christopher Li <sparse@chrisli.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Glauber Costa [Thu, 23 May 2013 00:37:23 +0000 (10:37 +1000)]
memcg: debugging facility to access dangling memcgs
If memcg is tracking anything other than plain user memory (swap, tcp buf
mem, or slab memory), it is possible - and normal - that a reference will
be held by the group after it is dead. Still, for developers, it would be
extremely useful to be able to query about those states during debugging.
This patch provides a debugging facility in the root memcg, so we can
inspect which memcgs still have pending objects, and what is the cause of
this state.
Signed-off-by: Glauber Costa <glommer@parallels.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Xi Wang [Thu, 23 May 2013 00:37:23 +0000 (10:37 +1000)]
mm/dmapool.c: fix null dev in dma_pool_create()
A few drivers invoke dma_pool_create() with a null dev. Note that dev is
dereferenced in dev_to_node(dev), causing a null pointer dereference.
A long term solution is to disallow null dev. Once the drivers are fixed,
we can simplify the core code here. For now we add WARN_ON(!dev) to
notify the driver maintainers and avoid the null pointer dereference.
Signed-off-by: Xi Wang <xi.wang@gmail.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Xi Wang [Thu, 23 May 2013 00:37:22 +0000 (10:37 +1000)]
drivers/usb/gadget/amd5536udc.c: avoid calling dma_pool_create() with NULL dev
Calling dma_pool_create() with dev==NULL will oops on a NUMA machine.
Rather than changing dma_pool_create() we wish to disallow passing
dev==NULL. This requires fixing up the small number of drivers which are
passing in dev==NULL.
Use &dev->pdev->dev instead of NULL.
Signed-off-by: Xi Wang <xi.wang@gmail.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Michal Hocko [Thu, 23 May 2013 00:37:22 +0000 (10:37 +1000)]
drop_caches: add some documentation and info message
I would like to resurrect Dave's patch. The last time it was posted was
here https://lkml.org/lkml/2010/9/16/250 and there didn't seem to be any
strong opposition.
Kosaki was worried about possible excessive logging when somebody drops
caches too often (but then he claimed he didn't have a strong opinion on
that) but I would say opposite. If somebody does that then I would really
like to know that from the log when supporting a system because it almost
for sure means that there is something fishy going on. It is also worth
mentioning that only root can write drop caches so this is not an flooding
attack vector.
I am bringing that up again because this can be really helpful when
chasing strange performance issues which (surprise surprise) turn out to
be related to artificially dropped caches done because the admin thinks
this would help...
I have just refreshed the original patch on top of the current mm tree
but I could live with KERN_INFO as well if people think that KERN_NOTICE
is too hysterical.
: From: Dave Hansen <dave@linux.vnet.ibm.com>
: Date: Fri, 12 Oct 2012 14:30:54 +0200
:
: There is plenty of anecdotal evidence and a load of blog posts
: suggesting that using "drop_caches" periodically keeps your system
: running in "tip top shape". Perhaps adding some kernel
: documentation will increase the amount of accurate data on its use.
:
: If we are not shrinking caches effectively, then we have real bugs.
: Using drop_caches will simply mask the bugs and make them harder
: to find, but certainly does not fix them, nor is it an appropriate
: "workaround" to limit the size of the caches.
:
: It's a great debugging tool, and is really handy for doing things
: like repeatable benchmark runs. So, add a bit more documentation
: about it, and add a little KERN_NOTICE. It should help developers
: who are chasing down reclaim-related bugs.
[mhocko@suse.cz: refreshed to current -mm tree]
[akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Mike Yoknis [Thu, 23 May 2013 00:37:22 +0000 (10:37 +1000)]
mm: memmap_init_zone() performance improvement
We have what we call an "architectural simulator". It is a computer
program that pretends that it is a computer system. We use it to test the
firmware before real hardware is available. We have booted Linux on our
simulator. As you would expect it takes longer to boot on the simulator
than it does on real hardware.
With my patch - boot time 41 minutes
Without patch - boot time 94 minutes
These numbers do not scale linearly to real hardware. But indicate to me
a place where Linux can be improved.
memmap_init_zone() loops through every Page Frame Number (pfn), including
pfn values that are within the gaps between existing memory sections. The
unneeded looping will become a boot performance issue when machines
configure larger memory ranges that will contain larger and more numerous
gaps.
The code will skip across invalid pfn values to reduce the number of loops
executed.
Signed-off-by: Mike Yoknis <mike.yoknis@hp.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cody P Schafer [Thu, 23 May 2013 00:37:20 +0000 (10:37 +1000)]
memory_hotplug: use pgdat_resize_lock() in __offline_pages()
mmzone.h documents node_size_lock (which pgdat_resize_lock() locks) as
follows:
* Must be held any time you expect node_start_pfn, node_present_pages
* or node_spanned_pages stay constant. [...]
So actually hold it when we update node_present_pages in __offline_pages().
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cody P Schafer [Thu, 23 May 2013 00:37:20 +0000 (10:37 +1000)]
memory_hotplug: use pgdat_resize_lock() in online_pages()
mmzone.h documents node_size_lock (which pgdat_resize_lock() locks) as
follows:
* Must be held any time you expect node_start_pfn, node_present_pages
* or node_spanned_pages stay constant. [...]
So actually hold it when we update node_present_pages in online_pages().
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cody P Schafer [Thu, 23 May 2013 00:37:20 +0000 (10:37 +1000)]
mmzone: note that node_size_lock should be manipulated via pgdat_resize_lock()
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cody P Schafer [Thu, 23 May 2013 00:37:19 +0000 (10:37 +1000)]
mm: fix comment referring to non-existent size_seqlock, change to span_seqlock
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Mel Gorman [Thu, 23 May 2013 00:37:19 +0000 (10:37 +1000)]
mm: vmscan: move logic from balance_pgdat() to kswapd_shrink_zone()
balance_pgdat() is very long and some of the logic can and should be
internal to kswapd_shrink_zone(). Move it so the flow of balance_pgdat()
is marginally easier to follow.
Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: Rik van Riel <riel@redhat.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Cc: Zlatko Calusic <zcalusic@bitsync.net> Cc: dormando <dormando@rydia.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Mel Gorman [Thu, 23 May 2013 00:37:19 +0000 (10:37 +1000)]
mm: vmscan: check if kswapd should writepage once per pgdat scan
Currently kswapd checks if it should start writepage as it shrinks each
zone without taking into consideration if the zone is balanced or not.
This is not wrong as such but it does not make much sense either. This
patch checks once per pgdat scan if kswapd should be writing pages.
Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Cc: Zlatko Calusic <zcalusic@bitsync.net> Cc: dormando <dormando@rydia.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Historically, kswapd used to congestion_wait() at higher priorities if it
was not making forward progress. This made no sense as the failure to make
progress could be completely independent of IO. It was later replaced by
wait_iff_congested() and removed entirely by commit 258401a6 (mm: don't
wait on congested zones in balance_pgdat()) as it was duplicating logic
in shrink_inactive_list().
This is problematic. If kswapd encounters many pages under writeback and
it continues to scan until it reaches the high watermark then it will
quickly skip over the pages under writeback and reclaim clean young
pages or push applications out to swap.
The use of wait_iff_congested() is not suited to kswapd as it will only
stall if the underlying BDI is really congested or a direct reclaimer was
unable to write to the underlying BDI. kswapd bypasses the BDI congestion
as it sets PF_SWAPWRITE but even if this was taken into account then it
would cause direct reclaimers to stall on writeback which is not desirable.
This patch sets a ZONE_WRITEBACK flag if direct reclaim or kswapd is
encountering too many pages under writeback. If this flag is set and
kswapd encounters a PageReclaim page under writeback then it'll assume
that the LRU lists are being recycled too quickly before IO can complete
and block waiting for some IO to complete.
Mel Gorman [Thu, 23 May 2013 00:37:18 +0000 (10:37 +1000)]
mm: vmscan: block kswapd if it is encountering pages under writeback
Historically, kswapd used to congestion_wait() at higher priorities if it
was not making forward progress. This made no sense as the failure to
make progress could be completely independent of IO. It was later
replaced by wait_iff_congested() and removed entirely by commit 258401a6
(mm: don't wait on congested zones in balance_pgdat()) as it was
duplicating logic in shrink_inactive_list().
This is problematic. If kswapd encounters many pages under writeback and
it continues to scan until it reaches the high watermark then it will
quickly skip over the pages under writeback and reclaim clean young pages
or push applications out to swap.
The use of wait_iff_congested() is not suited to kswapd as it will only
stall if the underlying BDI is really congested or a direct reclaimer was
unable to write to the underlying BDI. kswapd bypasses the BDI congestion
as it sets PF_SWAPWRITE but even if this was taken into account then it
would cause direct reclaimers to stall on writeback which is not
desirable.
This patch sets a ZONE_WRITEBACK flag if direct reclaim or kswapd is
encountering too many pages under writeback. If this flag is set and
kswapd encounters a PageReclaim page under writeback then it'll assume
that the LRU lists are being recycled too quickly before IO can complete
and block waiting for some IO to complete.
Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Cc: Zlatko Calusic <zcalusic@bitsync.net> Cc: dormando <dormando@rydia.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Mel Gorman [Thu, 23 May 2013 00:37:18 +0000 (10:37 +1000)]
mm: vmscan: have kswapd writeback pages based on dirty pages encountered, not priority
Currently kswapd queues dirty pages for writeback if scanning at an
elevated priority but the priority kswapd scans at is not related to the
number of unqueued dirty encountered. Since commit "mm: vmscan: Flatten
kswapd priority loop", the priority is related to the size of the LRU and
the zone watermark which is no indication as to whether kswapd should
write pages or not.
This patch tracks if an excessive number of unqueued dirty pages are being
encountered at the end of the LRU. If so, it indicates that dirty pages
are being recycled before flusher threads can clean them and flags the
zone so that kswapd will start writing pages until the zone is balanced.
Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Cc: Zlatko Calusic <zcalusic@bitsync.net> Cc: dormando <dormando@rydia.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Mel Gorman [Thu, 23 May 2013 00:37:17 +0000 (10:37 +1000)]
mm: vmscan: do not allow kswapd to scan at maximum priority
Page reclaim at priority 0 will scan the entire LRU as priority 0 is
considered to be a near OOM condition. Kswapd can reach priority 0 quite
easily if it is encountering a large number of pages it cannot reclaim
such as pages under writeback. When this happens, kswapd reclaims very
aggressively even though there may be no real risk of allocation failure
or OOM.
This patch prevents kswapd reaching priority 0 and trying to reclaim the
world. Direct reclaimers will still reach priority 0 in the event of an
OOM situation.
Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Cc: Zlatko Calusic <zcalusic@bitsync.net> Cc: dormando <dormando@rydia.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
projects / karo-tx-linux.git / log